Coarticulation is the kinematic and spectral overlap between adjacent sounds during speech production. Coarticulation patterns in typical adults have been well established; however, the manner in which coarticulation is developed in children is still unclear. Research has provided conflicting views, showing that children exhibit more, less, or an equal degree of coarticulation when compared to adult speakers. Considering the divergent findings present in the literature regarding coarticulation in children, the purpose of the present study is to further investigate anticipatory coarticulation in typically developing young children between the ages of three and six years. This study focuses on the acoustic characteristics of an unstressed vowel, the schwa, prior to a series of real words. Results indicate that children exhibit adult-like patterns of coarticulation even at a relatively young age. However, the degree of anticipatory coarticulation is dependent upon the phonemic context, with greater differences being evident in a fricative context and less when followed by a stop consonant.

Electropalatometry (EPM) has proven to be a useful clinical and research tool for measuring tongue-to-palate contact. The goal of this study was to determine whether the development of a database of standardized palatometric articulation files is feasible by examining the variability which exists within and between speakers. Twenty standard American English dialect speakers were fitted with palatometer pseudopalates. Test stimuli were VCV nonsense words using a schwa in the initial position, the 15 palatal consonants, and three corner vowels, /a/, /i/, /u/. From these palatometric recordings a variability index was created to examine intra- and interspeaker variability. Different aspects of articulation (i.e., place, manner, voicing, coarticulation) were considered. Significant findings for variability were found for place of articulation in the /i/ vowel context and for manner of articulation in the /ɑ/ vowel context. Also in the /a/ vowel context, significant findings were found between the commonly misarticulated /l/, /r/, and /s/. Consonants coarticulated with /a/ were found to be significantly less variable than consonants coarticulated with /u/. Also, speakers who were more variable in one vowel context, tended to be more variable in other vowel contexts. These quantitative findings, as well as qualitative observations, are discussed from theoretical and clinical perspectives. Directions for future research are outlined.

Speech recognition thresholds are used for several clinical purposes, so it is important that they be accurate reflections of hearing ability. Variations in the acoustic signal may artificially decrease threshold scores, and such variations can result from being tested in a second dialect. Thirty-two native Mandarin-speaking subjects (sixteen from mainland China and sixteen from Taiwan) participated in speech recognition threshold testing in both dialects to see whether using non-native dialect test materials resulted in a significantly lower score. In addition, tests were scored by two interpreters, one from each dialect, to see whether the scorer's dialect resulted in a significantly different score. Talker dialect was found to be statistically significant, while scorer dialect was not. Factors explaining these findings, as well as clinical implications, are discussed.

Dual task performance and the interaction of tasks has been the subject of much research. When tasks are performed together they affect each other to varying degrees depending upon such factors as the similarity of the tasks, their difficulty, and whether one task is given preference over another. In this study, task preference was investigated under divided attention conditions in order to determine what effect preference had on task performance. Twenty young adults took part in this study and were randomly assigned into two groups. Each group was experimentally motivated to favor one of the two tasks – either speaking a "tongue-twister" or tracking a moving target on a screen with a computer mouse. Each participant performed the tasks in both an isolated and combined conditions. The measurements of task performance (tracking scores, utterance duration, lower lip and jaw displacement, lower lip and jaw velocity, upper lip-lower lip correlation, spatiotemporal index, and sound pressure level) were then analyzed to determine how task preference affected the participant's performance. It was expected that the preferred task's performance would not suffer when performed in the dual task situation. Although some trends were noted in the predicted direction, no statistically significant results were found as a function of task preference. There were, however, some gender effects. Men were found to have significantly higher intensity than women during the speaking tasks in both the dual and isolated task conditions, and they were also found to perform better than women on the motor tracking task in both the dual and isolated task conditions.

The purpose of this study was to develop, digitally record, evaluate, and psychometrically equate a set of Tongan bisyllabic word lists for use in measurement of word recognition testing. Commonly used bisyllabic words were digitally recorded by male and female native talkers of Tongan. The psychometric performance of the words was measured at ten intensity levels (- 5 to 40 dB HL) in 5 dB increments by 20 listeners with normal hearing acuity. The 200 words with the highest rate of listener identification were included in four relatively psychometrically equivalent word lists of 50 words each and eight half-lists of 25 words each. Using logistic regression, the mean psychometric slope across the created word lists at 50% intelligibility was found to be 6.3%/dB for materials created from the male talker recordings and 6.2%/dB for the female talker recordings. To increase auditory homogeneity of the word recognition lists, the intensity of words in each list was digitally adjusted so that the threshold of each list was equal to the midpoint between the mean thresholds of the male and female half-lists. Digital recordings of the psychometrically equivalent word recognition lists are available on compact disc.

Recent literature has suggested a link between verbal working memory and language impairment (LI) in children. There is limited research, however, about the link between verbal working memory and social behaviors in children with LI. This study was designed to explore the relationship between social behaviors (measured by the Teacher Behavior Rating Scale; Hart & Robinson, 1996) and verbal working memory abilities (measured by a 3-, 4-, and 5-syllable nonword repetition task) in children with LI. Thirty-six children (18 with LI and 18 typically developing) aged 7 to 11 years participated in the study. Children with LI were rated by teachers as having significantly higher levels of reticence and lower levels of likeability and prosocial behaviors compared to typically developing peers. Children with LI also scored significantly lower on the nonword repetition task at the 3- and 4-syllable levels. Regression analyses revealed that nonword repetition scores were significant predictors of reticence and prosocial behaviors when examining all children as a group, accounting for 22% and 42% of the variance, respectively. As nonword repetition performance increased, reticence ratings decreased and prosocial behavior ratings increased. Nonword repetition did not significantly predict ratings on reticence or prosocial behaviors when examining language groups separately. Nonword repetition was not a significant predictor of likeability for children in this study. These findings indicate a relationship between nonword repetition performance and social behaviors in children with and without LI.

Several recent studies indicate that children with Language Impairment (LI) have difficulty recognizing and inferring meaning from emotional prosody. The present study is a replication investigating the ability of children with LI to recognize emotion conveyed by prosody in an orally presented narrative passage. Twenty-two children with LI and twenty-two age matched peers ranging from age 7;0 to 10;11 (M= 9.11, SD= 2.54) were selected to participate. Participants listened to recordings of a seven sentence passage read by actors to express happiness, anger, sadness, and fear. The children's task was to identify which emotion the speaker portrayed. Scores obtained from the children with LI as a group were significantly lower than the scores of typically developing children. Differences in the degree of recognition of individual emotions were also apparent; happiness being correctly identified most frequently, followed by anger, sadness, and then fear. Evidence supports the supposition that children with LI struggle to understand emotion conveyed through prosodic cues, which may contribute to the social challenges children with LI experience.

Both acoustic and palatographic measures have proven to be useful in speech science research. However, it is not known how closely or consistently these two measures are associated with each other. Therefore, this study investigated the association between changes in tongue-to-palate contact patterns and simultaneous changes in acoustic spectral moments for the fricative /s/. Twenty adults were fitted with pseudopalates and repeated VCV nonsense syllables consisting of an initial schwa followed by the target consonant /s/ and ending with one of three corner vowels (/i, ɑ, u/). EPG (electropalatography) data were quantified using three custom numerical indices (s-narrow, s-wide, and asymmetry) derived from specified zones on the pseudopalate which loosely reflected dimensional differences in the fricative groove. These indices produced general details about changes in tongue contact over time, but index values were not unique to specific contact patterns. The EPG numerical index values were then compared with differences in spectral moments (spectral mean and variance) from the time-aligned acoustic signal. On the whole, all combinations of spectral mean and variance and EPG indices resulted in some weak but significant correlations across all vowel contexts and participant groupings. The majority of these correlations were negative, meaning that as EPG index values increased, spectral mean and variance decreased. Some of the strongest of these correlations were present between s-narrow and spectral mean and variance. Therefore, in order to give a clearer picture of the link between lingual physiology and spectral moments, these variables were correlated for each individual speaker. Stronger significant correlations between s-narrow and both spectral mean and variance were identified in some participants. The majority of these correlations were also negative, suggesting that as the s-narrow index increased, the spectral mean and the variance decreased. A few participants' results that showed interesting lingua-palatal contact patterns are discussed in more detail. Generalization based on specific correlations from this study must be undertaken with considerable caution due to desynchronization of EPG data and the acoustic signal found in several tokens.

Phonemic categorization is the ability to discriminate and organize speech sounds into categories. This ability begins soon after birth and continues to refine as an individual matures. An association between categorical labeling and phonological awareness has been reported. A strong link between perception and production has been established. The present study examined phonemic categorization of two groups of four listeners. Eight-to ten-year-old children with an articulation disorder were compared with typically speaking peers to determine if the two groups differed in their ability to categorize speech sounds. Behavioral and electrophysiological measures were used to ascertain if any differences existed. These measures were obtained in response to four stimulus pairs (/pɑ/-/tɑ/, /tɑ/-/kɑ/, /pɑ/-/kɑ/, /sɑ/-/ʃɑ/). Three of the pairs (/pɑ/-/tɑ/, /tɑ/-/kɑ/, /pɑ/-/kɑ/) differed by place of articulation only and the fourth pair (/sɑ/-/ʃɑ/) consisted of sounds that are more commonly found in error for the age group of the participants. Behavioral data showed differences in reaction time between the two groups as well as between correct and incorrect responses. Electrophysiological data including the mismatch negativity showed that both groups perceived a distinction between the stimuli presented, but the normal control group generally displayed a higher SD for peak latency and amplitude. The normal control group also generally displayed a higher mean amplitude. These results suggest a difference between the two groups in the underlying processes of phonemic categorization. Specifically, these results support that the normal control group's ability to distinguish and categorize speech sounds is better established than that of their peers with an articulation disorder.

This study investigated the ability of children with LI to recognize the need to dissemble emotions. Participants included 22 children with LI and 22 typically developing peers, ages 7;1 to 11;0 years. Children were presented with 10 hypothetical social scenarios in which the main character experienced an emotion which should be dissembled for social purposes. The participant's responses were categorized as dissemblance or display. Children with LI reported that they would hide the experienced emotion significantly less often than their typical peers. Children in both groups reported higher levels of dissemblance when asked what their parents would want them to do. There was no significant difference between language groups for this question.